//-------------------------------------------------------------------------
// Copyright (c) 2000-2010 Digital. All Rights Reserved.
//
// This software is the confidential and proprietary information of
// Digital
//
// Original author: fangyong
//
//-------------------------------------------------------------------------
// LOOSOFT MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE SUITABILITY OF
// THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
// TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
// PARTICULAR PURPOSE, OR NON-INFRINGEMENT. UFINITY SHALL NOT BE
// LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING,
// MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
//
// THIS SOFTWARE IS NOT DESIGNED OR INTENDED FOR USE OR RESALE AS ON-LINE
// CONTROL EQUIPMENT IN HAZARDOUS ENVIRONMENTS REQUIRING FAIL-SAFE
// PERFORMANCE, SUCH AS IN THE OPERATION OF NUCLEAR FACILITIES, AIRCRAFT
// NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL, DIRECT LIFE
// SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH THE FAILURE OF THE
// SOFTWARE COULD LEAD DIRECTLY TO DEATH, PERSONAL INJURY, OR SEVERE
// PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH RISK ACTIVITIES"). UFINITY
// SPECIFICALLY DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR
// HIGH RISK ACTIVITIES.
//-------------------------------------------------------------------------
package com.gm.flower.servlet;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

/**
 * 
 * 验证码servlet
 * 
 * @author qingang
 * @version 1.0
 * @since 2013-1-29
 */
public class AuthImg extends HttpServlet {
	/**
	 * serialVersionUID long
	 */
	private static final long serialVersionUID = 1L;
	private final Font mFont = new Font("Arial Black", Font.PLAIN, 18);

	@Override
	public void init() throws ServletException {
		super.init();
	}

	Color getRandColor(int fc, int bc) {
		Random random = new Random();
		if (fc > 255) {
			fc = 255;
		}
		if (bc > 255) {
			bc = 255;
		}
		int r = fc + random.nextInt(bc - fc);
		int g = fc + random.nextInt(bc - fc);
		int b = fc + random.nextInt(bc - fc);
		return new Color(r, g, b);
	}

	@Override
	public void service(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		response.setHeader("Pragma", "No-cache");
		response.setHeader("Cache-Control", "no-cache");
		response.setDateHeader("Expires", 0);
		response.setContentType("image/jpeg");

		int width = 70, height = 23;
		BufferedImage image = new BufferedImage(width, height,
				BufferedImage.TYPE_INT_RGB);

		Graphics g = image.getGraphics();
		Random random = new Random();
		g.setColor(getRandColor(200, 250));
		g.fillRect(1, 1, width - 1, height - 1);
		g.setColor(new Color(102, 102, 102));
		g.drawRect(0, 0, width - 1, height - 1);
		g.setFont(mFont);

		g.setColor(getRandColor(160, 200));
		for (int i = 0; i < 155; i++) {
			int x = random.nextInt(width - 1);
			int y = random.nextInt(height - 1);
			int xl = random.nextInt(6) + 1;
			int yl = random.nextInt(12) + 1;
			g.drawLine(x, y, x + xl, y + yl);
		}
		for (int i = 0; i < 70; i++) {
			int x = random.nextInt(width - 1);
			int y = random.nextInt(height - 1);
			int xl = random.nextInt(12) + 1;
			int yl = random.nextInt(6) + 1;
			g.drawLine(x, y, x - xl, y - yl);
		}
		String sRand = "";
		for (int i = 0; i < 4; i++) {
			String tmp = getRandomChar();
			sRand += tmp;
			g.setColor(new Color(20 + random.nextInt(110), 20 + random
					.nextInt(110), 20 + random.nextInt(110)));
			g.drawString(tmp, 15 * i + 10, 15);
		}
		HttpSession session = request.getSession(true);
		session.setAttribute("scode", sRand);
		g.dispose();
		ImageIO.write(image, "JPEG", response.getOutputStream());
	}

	private String getRandomChar() {
		int rand = (int) Math.round(Math.random() * 2);
		long itmp = 0;
		char ctmp = '\u0000';
		switch (rand) {
		case 1:
			itmp = Math.round(Math.random() * 25 + 65);
			ctmp = (char) itmp;
			return String.valueOf(ctmp);
		case 2:
			itmp = Math.round(Math.random() * 25 + 97);
			ctmp = (char) itmp;
			return String.valueOf(ctmp);
		default:
			itmp = Math.round(Math.random() * 9);
			return String.valueOf(itmp);
		}
	}
}
